At the moment, I'm into slouchy bags like the MJ Faridah or Juicy leather hobos. However, I find that things tend to get lost in slouchy bags and it takes me longer to find stuff.
I like the structured bags the best. I feel like I don't know how to "pack" the bag if it moves around too much. If it is structured, I know exactly where things are and they aren't getting moved around too much.
With that said, I don't like them to be too stiff. If I want to get something out of it real quick, I don't want to feel like I am cutting my hand on the zipper. I do have to say that I am a clean line person and, for cryin' out loud, I can't stand folds in my money. You're damn right I have ironed it!